An organic EL device is constituted of counter electrodes having a luminescent layer and a plurality of organic layers containing a luminescent layer put therebetween. The organic EL device is a device for obtaining luminescence utilizing either one of luminescence from excitons formed by recombination of electrons injected from a cathode and holes injected from an anode in a luminescent layer, or luminescence from excitons of other molecule formed by energy transfer from the foregoing excitons.
An invention directed to a phosphorescent organic EL element using a metal complex as a host material is disclosed (see JP-A-2002-305083). However, it is the present state that its luminous efficiency and durability are not yet sufficient, and hence, development of devices exhibiting higher luminance and luminous efficiency and having excellent durability is eagerly demanded.